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1.
Heliyon ; 10(5): e26986, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38455548

ABSTRACT

The COVID-19 pandemic has greatly changed global practices of enterprise digital transformation (EDT). However, the impact of the pandemic on EDT research patterns remains unexplored. This study examines the overall development and research pattern shift of literature on EDT in the field of business and economics. A bibliometric analysis with CiteSpace was conducted on a total of 140 journal articles indexed the SSCI and SCIE databases on Web of Science prior to the pandemic and 621 articles published after the pandemic. The results suggest that following the outbreak of COVID-19 pandemic, there has been a significantly rapid growth of EDT-related publications, and the contributing role in EDT research of influential countries has undergone significant changes. Furthermore, the changes in keyword patterns were identified before and after the pandemic. Specifically, EDT research after the COVID-19 outbreak has been focusing on emerging topics, such as corporate governance, sustainable development, platform ecosystems, and dynamic capabilities. Finally, recommendations for future research are provided at individual, organizational, and ecosystem levels. Overall, this study is one of the first studies to uncover the dynamics of EDT research patterns due to the COVID-19 Pandemic, thus enhancing our understanding of the features and structures of digital transformation research in uncertain environment.

2.
Bioanalysis ; 15(12): 661-671, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37431827

ABSTRACT

Aim: This study aimed to investigate the gas chromatographic properties and mass spectrometric fragmentations of anabolic androgenic steroids (AASs) after trimethylsilylated derivatization. Materials & methods: A total of 113 AASs were analyzed through gas chromatography-mass spectrometry in the full-scan mode. Results: New fragmentation pathways yielding m/z 129, 143 and 169 ions were analyzed. Based on the characteristics of the A-ring, seven classes of drugs were identified and analyzed. Conclusion: The fragmentation pathway of a new classification of 4-en-3-hydroxyl was reported for the first time. The relationship between the chemical structures of AASs and their retention time, along with their molecular ion peak abundance, was also reported herein for the first time.


Subject(s)
Anabolic Agents , Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Anabolic Androgenic Steroids , Anabolic Agents/analysis , Steroids/analysis , Mass Spectrometry , Ions
3.
Bioanalysis ; 12(11): 783-790, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32441534

ABSTRACT

Aim: Follow-up investigations are often required for clenbuterol-positive cases. A method to distinguish doping abuse from meat contamination was developed. Materials & methods: A total of 26 volunteers were recruited to ingest clenbuterol contaminated-pork and clenbuterol tablets. Results: For 20 volunteers, after ingestion of contaminated-pork, R-(-)/S-(+)-clenbuterol ratio was <1.0, while the value was >1.0 after taking clenbuterol tablets. However, after taking clenbuterol tablets, some ratio points of the other six volunteers were between 0.9 and 1.0. A case of an abnormal cold and fever, which returned to normal after recovery, was also reported firstly. Conclusion: A change in R-(-)/S-(+)-clenbuterol was reported in the Chinese population initially. A ratio of 0.9 was recommended in doping related cases for the Chinese population.


Subject(s)
Clenbuterol/urine , Doping in Sports , Food Contamination/analysis , Meat/analysis , Performance-Enhancing Substances/urine , Substance Abuse Detection , Animals , Asian People , Chromatography, Liquid , Female , Humans , Male , Stereoisomerism , Swine , Tandem Mass Spectrometry
4.
Molecules ; 19(1): 1212-22, 2014 Jan 20.
Article in English | MEDLINE | ID: mdl-24448062

ABSTRACT

Antidepressants are a new kind of pollutants being increasingly found in wastewater. In this study, a fast and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry method was developed and validated for the analysis of 24 antidepressant drugs and six of their metabolites in wastewater. This is the first time that the antidepressant residues in wastewater of Beijing (China) were systematically reported. A solid-phase extraction process was performed with 3 M cation disk, followed by ultra-high performance liquid chromatography-tandem mass spectrometry measurements. The chromatographic separation and mass parameters were optimized in order to achieve suitable retention time and good resolution for analytes. All compounds were satisfactorily determined in one single injection within 20 min. The limit of quantification (LOQ), linearity, and extraction recovery were validated. The LOQ for analytes were ranged from 0.02 to 0.51 ng/mL. The determination coefficients were more than 0.99 within the tested concentration range (0.1-25 ng/mL), and the recovery rate for each target compound was ranged from 81.2% to 118% at 1 ng/mL. This new developed method was successfully applied to analysis the samples collected from Beijing municipal wastewater treatment plants. At least ten target antidepressants were found in all samples and the highest mean concentration of desmethylvenlafaxin was up to 415.6 ng/L.


Subject(s)
Antidepressive Agents/analysis , Wastewater/analysis , Water Pollutants, Chemical/analysis , Antidepressive Agents/isolation & purification , Chromatography, High Pressure Liquid , Humans , Limit of Detection , Solid Phase Extraction , Tandem Mass Spectrometry , Water Pollutants, Chemical/isolation & purification , Water Purification
5.
PLoS One ; 8(4): e61922, 2013.
Article in English | MEDLINE | ID: mdl-23613974

ABSTRACT

Hyperlipidemia is considered to be one of the greatest risk factors contributing to the prevalence and severity of cardiovascular diseases. In this work, we investigated the anti-hyperlipidemic effect and potential mechanism of action of the Pandanus tectorius fruit extract in hamsters fed a high fat-diet (HFD). The n-butanol fraction of the P. tectorius fruit ethanol extract (PTF-b) was rich in caffeoylquinic acids (CQAs). Administration of PTF-b for 4 weeks effectively decreased retroperitoneal fat and the serum levels of total cholesterol (TC), triglycerides (TG) and low density lipoprotein-cholesterol (LDL-c) and hepatic TC and TG. The lipid signals (fatty acids, and cholesterol) in the liver as determined by nuclear magnetic resonance (NMR) were correspondingly reduced. Realtime quantitative PCR showed that the mRNA levels of PPARα and PPARα-regulated genes such as ACO, CPT1, LPL and HSL were largely enhanced by PTF-b. The transcription of LDLR, CYP7A1, and PPARγ was also upregulated. Treatment with PTF-b significantly stimulated the activation of AMP-activated protein kinase (AMPK) as well as the activity of serum and hepatic lipoprotein lipase (LPL). Together, these results suggest that administration of the PTF-b enriched in CQAs moderates hyperlipidemia and improves the liver lipid profile. These effects may be caused, at least in part, by increasing the expression of PPARα and its downstream genes and by upregulation of LPL and AMPK activities.


Subject(s)
Diet, High-Fat/adverse effects , Fruit/chemistry , Hypolipidemic Agents/therapeutic use , Pandanaceae/chemistry , Plant Extracts/therapeutic use , Quinic Acid/analogs & derivatives , Animals , Cholesterol/blood , Cholesterol/metabolism , Cholesterol, LDL/blood , Cholesterol, LDL/metabolism , Cricetinae , Lipid Metabolism/drug effects , Liver/drug effects , Liver/metabolism , Quinic Acid/therapeutic use , Triglycerides/blood , Triglycerides/metabolism
6.
Life Sci ; 90(1-2): 1-7, 2012 Jan 02.
Article in English | MEDLINE | ID: mdl-21939670

ABSTRACT

AIMS: Our overall objective was to investigate the effect of the adenosine derivative 2',3',5'-tri-O-acetyl-N6-(3-hydroxylaniline) adenosine (WS010117) on AMP-activated protein kinase (AMPK) activation and lipid metabolism and to also assess the underlying mechanisms involved in these processes. MAIN METHODS: HepG2 cells and hamsters fed a high-fat diet were used to test the effects of WS010117 on lipid metabolism. Western blots, chemical intervention, HPLC, SAMS peptide assay, (14)C-labelled acetate and palmitate assays, molecular docking assay and siRNA targeting the AMPK γ1 subunit were used to investigate the effect of WS010117 on AMPK activation as well as the underlying mechanism involved in this activation. KEY FINDINGS: WS010117 treatment resulted in the dose-dependent activation of AMPK in HepG2 cells, increasing lipid oxidation and decreasing lipid biosynthesis. In hamsters that were fed a high-fat diet, WS010117 treatment (1.5-6 mg/kg) significantly inhibited the increase in lipid accumulation. WS010117-induced AMPK activation was essentially abolished by treatment with compound C, and the addition of WS010117 did not alter the intracellular AMP:ATP ratio. In HeLa cells endogenously lacking LKB1, WS010117-mediated AMPK activation was not impaired, even following co-treatment with STO-609, a selective inhibitor of Ca(2+)/calmodulin-dependent protein kinase kinase (CaMKK). The results from the molecular docking assays and experiments targeting the AMPK γ1 subunit with siRNA indicated that WS010117 may activate AMPK by binding to and regulating the γ subunit of AMPK. SIGNIFICANCE: Our data indicate that WS010117 can regulate lipid metabolism through the activation of AMPK. WS010117 may activate AMPK by binding to and regulating the AMPK γ subunit.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Adenosine/analogs & derivatives , Dietary Fats/antagonists & inhibitors , Lipid Metabolism/drug effects , AMP-Activated Protein Kinases/antagonists & inhibitors , Adenosine/administration & dosage , Adenosine/pharmacology , Adenosine/physiology , Animals , Cells, Cultured , Cricetinae , Dietary Fats/administration & dosage , Dietary Fats/metabolism , Enzyme Activation/drug effects , Enzyme Activation/physiology , HeLa Cells , Hep G2 Cells , Humans , Lipid Metabolism/physiology , Male , Mesocricetus , Pyrazoles/pharmacology , Pyrimidines/pharmacology
7.
Phytomedicine ; 18(4): 292-7, 2011 Feb 15.
Article in English | MEDLINE | ID: mdl-20739161

ABSTRACT

Belamcanda chinensis (Iridaceae) belongs to the family of iridaceae and its rhizoma has been widely used for the treatment of throat ailment. Here we report a new pharmacological activity of B. chinensis leaf extract (BCL), that is, the hypoglycemic effect in normal and STZ-induced diabetic rats. Animals either healthy or STZ-induced diabetic show significantly lowered fasting blood glucose levels after treatment with BCL. The serum insulin concentration in normal rats is also enhanced. Additionally, the increase in blood glucose levels after administration of various carbohydrates in normal rats is significantly decreased and the oral glucose tolerance (OGTT) of STZ-induced diabetic rats is largely improved by BCL treatment. However, co-administration of BCL with Nifedipine, a Ca(2+) ion channel blocker, or Nicorandil, an ATP-sensitive K(+) ion channel opener thoroughly abolishes the hypoglycemic effect of BCL. HPLC analysis and compound identification showed that several isoflavone glycosides with antidiabetic activities were contained in BCL while pharmacological experiment showed that the polysaccharide fraction of BCL had no significant hypoglycemic effect on normal rats. Therefore, the isoflavone glycosides but not polysaccharides might be the active fraction of BCL in diabetes treatment.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/therapeutic use , Iridaceae/chemistry , Phytotherapy , Plant Extracts/therapeutic use , Animals , Blood Glucose/metabolism , Calcium/metabolism , Calcium Channels/drug effects , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Glucose Tolerance Test , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/pharmacology , Insulin/blood , Male , Nicorandil/pharmacology , Nifedipine/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Potassium/metabolism , Potassium Channels/drug effects , Rats , Rats, Wistar , Streptozocin/toxicity
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